The design is retarded. The fans should be installed in the top part of the case where the CPU and GPU are. In the lower part, all they do is make noise and cool hard drives.
Check the HAF XB for a proper "stacker" case design.
Not using a regular-sized DVD drive is a bad idea in a case this large. Choice is very poor for these drives, and there's plenty of arguably wasted space in this case anyway.
I think the layout and space usage is very questionnable.